Radio frequency identification (RFID) tags are well known for electronic identification and tracking of items. A variety of industries, such as retail establishments, warehousing, shipping, inventory systems, product and component maintenance and tracking systems, and many others, employ RFID tags for electronic identification and tracking of items as they proceed through such systems.
RFID systems may be passive or active. In a passive RFID system, an RFID tag may contain small integrated circuitry embedded within the tag. The tag circuitry may function both as a radio receiver and transmitter, as well as an electronic data storage medium, and a tuned conductor which acts as an antenna. In passive systems, energy from the reader energizes the circuitry in the tag, which in turn emits a signal that may be read by the reader. The signal may then be associated with component or item information that may be stored in the tag circuitry itself, and/or in a remote database. In an active RFID system, the tag additionally may have an onboard power source to boost performance.
In typical examples, the RFID tag may be fixed onto an outer surface of the tagged article with any suitable type of bonding. The tag, therefore, may be exposed to the environment. As the tags are generally relatively thin sheets of material, tags are easily worn and damaged by adverse environmental conditions. The metal tag base and embedded circuitry are thus fragile, which can result in frequent need to replace the tags.
Applicant's commonly owned U.S. Pat. No. 8,282,013 (Stewart et al., issued Oct. 9, 2012) teaches to provide a ruggedized RFID tag in the context of a sealing element, such as an o-ring or other geometric closed-shape elastomeric sealing element. In the '013 patent, the RFID tag or transponder is embedded within the elastomeric material of the sealing element, particularly during a molding process for manufacturing the sealing element. The method disclosed in the '013 patent generally includes inserting one or more tags or transponders into a preformed sealing element, and then subjecting the preformed sealing element to additional processing such as heat compression or other molding to form the final sealing element. The '013 patent is particularly suitable for RFID systems, as the electronic signals of the tag and reader can pass through the sealing material.
In the '013 patent, the tag typically is associated with information pertaining to the sealing element itself, and not to the broader article into which the sealing element is used. In many systems, it may be desirable to have tags associated with information pertaining to both a generalized article and components thereof, and to have a tag assembly that can be readily removed, reprogrammed, and replaced onto the same or a different article or component. The methods of the '013 patent, therefore, constitute improvements over conventional attempts to ruggedize an RFID tag, but there remains additional need to improve over the various conventional RFID tagging systems.